Due to educational developments and the inefficiency of traditional teaching models, the role of teacher leadership in schools has gained special importance. This qualitative research, using the systematic data-based theory approach of Strauss and Corbin (1997), examined the dimensions of teacher leadership in Iranian schools. Data collection was conducted through semi-structured interviews with teachers, principals, and professors in Sanandaj city and continued until theoretical saturation was reached. Data analysis was performed using MAXQDA (2020) software in three stages: open, axial, and selective coding. In open coding, 302 initial codes were extracted and, after merging, were organized into 66 axial codes. In selective coding, 18 selective categories were formed, which formed the final structure of the model. Paradigmatic model including contextual conditions (centralized structure, traditional culture, work pressure), causal conditions (changing educational needs and inefficiency of traditional teaching), Intervening conditions (the role of the manager, organizational support, in-service training), pivotal phenomenon (the emergence of the teacher leader as an agent of change), The strategies were (empowerment, learning networks, creativity, and teamwork) and the outcomes (increasing motivation, improving the quality of learning, strengthening professional identity, and collaborative culture). This research, while aligning with international studies, presented a local picture of teacher leadership in Iran and demonstrated the need for structural and cultural reforms to respond to today's educational challenges.